Usually, a broadcast station expands the receiving area of broadcasting by installing a relay station at a plurality of locations within a broadcast area and sending broadcast radio waves from these relay stations. If a relay station sends a broadcast radio wave at the same frequency (SFN: Single Frequency Network), a program can be continuously viewed even if a movable body moves to other receiving area. However, if a relay station sends a broadcast radio wave at different frequency (MFN: Multi Frequency Network), when a movable body moves to other receiving area, a program that has been viewed till then cannot be received.
For this reason, particularly in a broadcast receiver device mounted on a movable body, such as a car, when it moves to other receiving area and cannot receive a program that has been viewed, there is a need to carry out channel search, search the broadcast radio wave of a receivable relay station and reestablish the channel in order to continuously view the program. While carrying out this channel search, there is an inconvenience that the program cannot be viewed.
In view of the above circumstances, patent Literature 1 discloses a method in which a main tuner for receiving programs and a sub-tuner for executing channel search are provided, and the reception intensity of each frequency is detected by searching all frequency ranges with the sub-tuner, channels having reception intensities which are equal to or higher than a threshold intensity is determined to be receivable, and the time to search channels is shortened by causing the main tuner to search only these channels.